Ben,
I'd watch it for sure, but I think snorvich has a point about the business model. You rarely even see home aquariums mentioned in pet columns for newspapers. After Guppies to Groupers went off the air, there was one syndicated radio show that dealt with fish (Pet Talk Radio). I think it is only a podcast now. I went on it once, it aired at 10pm and again at 2am - the audience was mostly truck drivers and other people driving around at night. National aquarium magazines rarely have paid circulation higher than 40,000 copies per month, and a "bestselling" book on aquariums is one that sells more than 10,000 copies in five years.
We've done a few segments about home aquariums for a regional television show "Zoo Today" and more recently, a two minute spot on our local news "what a zoo". One of my aquarists just did a segment on Friday about "Nemo" and how to avoid problems getting into this hobby. I always had trouble distilling aquarium topics done to a sound bite - can you imagine trying to discuss treating Cryptocaryon in two minutes? Or the ethical issues of buying fish that grow too large?
On the other hand - as a device to actually increase participation in this hobby, a show like you describe could be of real benefit. Hopefully some of the more forward-thinking manufacturers will realize this and help subsidize it.
JHemdal